1. Field of the Invention
This invention relates to a device that uses a fluid to dampen a force which tends to move the plane of rotation of a steerable wheel or wheels of a vehicle having a shaft used to steer such wheel or wheels away from being generally parallel to the frame of such vehicle. It also relates to such a device for any steering mechanism, such as a ski of a snowmobile or the exhaust jet of a personal watercraft, that uses a shaft of the like and a handlebar or the like in the steering process. For convenience, the term “motorcycle” will be used herein; this term includes, through, not only a traditional motorcycle but also any vehicle using a steering mechanism as discussed in the preceding sentence.
2. Description of the Related Art
Dampening devices of the type subject to the present invention are those which contain a rotatable wiper (also called a vane) in a housing having a channel (or circuit) running from a portion of the housing on or near a first side of the wiper to a portion of the housing on or near a second side of the wiper so that when the housing is filled with fluid, as the wiper is moved, it forces fluid through the channel (or circuit). Such devices are herein termed either dampeners or stabilizers with the two terms being considered synonymous with one another.
Examples of such devices are those of U.S. Pat. Nos. 4,773,514; 6,401,884; U.S. patent application Ser. Nos. 10/801,626; and 11/062,278.
Generally, some form of valve is placed within the channel (or circuit) in order to control the degree of dampening. This is usually accomplished by varying the effective cross-sectional area of the channel (or circuit).
In the rotary damper of U.S. Pat. No. 6,899,208 the wiper consists of two types of elements—at least two paddle 13, 14 extend outward from a rotor 11. An orifice 27 on each side of each wiper 13, 14 proceeds linearly into the hollow center of the rotor 11, the orifices 27 and the hollow center of the rotor 11 thereby creating the channel (or circuit) within the rotor 11 portion of the wiper, rather than having the channel (or circuit) within the housing, or proceeding from the internal chamber of the housing through the housing into tubes leading from and subsequently returning back to the housing (as is done in U.S. Pat. No. 6,802,519 and in U.S. patent application Ser. No. 11/062,278).
The valve in the rotary damper of U.S. Pat. No. 6,899,208 is, according to lines 30 through 39 of column 2, simply a plug that is screwed up or down to increase the volume within the hollow center of the rotor 11: “The preferred embodiment contemplates a centrally located flow regulator 29 can be adjusted vertically by means of a threaded shaft 30 that is turned by a knob 31 on top of the damper. The shaft 30 is sealed by means of an o-ring at 32. The regulator 29 has a cylindrical surface on its circumference at 33 that will move vertically up and down blocking a portion and therefore reducing or increasing the size of the orifices 27 thereby causing variation in the damping effect.”
In U.S. patent application Ser. No. 10/166,498, which was filed on Jun. 10 2002; United Kingdom patent no. 2 389 637, the application for which was filed on Jun. 10, 2002; U.S. Pat. No. 6,802,519, the application for which was filed on Sep. 9, 2002; and U.S. patent application Ser. No. 11/062,278, which was filed on Feb. 17, 2005, the valve is in a channel (or circuit) within the housing, or proceeding from the internal chamber of the housing through the housing into tubes leading from and subsequently returning back to the housing and comprises a shaft with a groove of increasing cross-sectional area, preferably created by the groove increasing in depth linearly as the groove proceeds around the shaft, which exists only part of the way around the shaft. The valve, therefore, depending upon the rotational position of the shaft, either completely or partially occludes the channel (or circuit) thereby varying and, hence, controlling the flow of fluid and, consequently, the damping created by the stabilizer.
Movement of the wiper relative to the housing is achieved by connecting the housing to the handlebars or to the shaft through which the handlebars turn the form wheel of a motorcycle or other steering mechanism, as discussed above, while rotatably attaching the wiper to the frame of the motorcycle. An arm is generally connected to the wiper. This arm may have the traditional aperture through which a pin rigidly attached to the frame of the motorcycle extends or may be of a pinless variety that has no aperture but is held within a yoke. This latter version is described in copending U.S. patent application Ser. No. 11/700,994.
Finally, a ball detent is a well-known mechanism for controlling the rotation of a wheel or know.